<?php
declare(strict_types=1);
namespace Doctrine\DBAL\Portability;
use function array_change_key_case;
use function array_map;
use function array_reduce;
use function is_string;
use function rtrim;
final class Converter
{
/** @var callable */
private $convertNumeric;
/** @var callable */
private $convertAssociative;
/** @var callable */
private $convertOne;
/** @var callable */
private $convertAllNumeric;
/** @var callable */
private $convertAllAssociative;
/** @var callable */
private $convertFirstColumn;
/**
* @param bool $convertEmptyStringToNull Whether each empty string should be converted to NULL
* @param bool $rightTrimString Whether each string should right-trimmed
* @param int|null $case Convert the case of the column names
* (one of {@link CASE_LOWER} and {@link CASE_UPPER})
*/
public function __construct(bool $convertEmptyStringToNull, bool $rightTrimString, ?int $case)
{
$id =
/**
* @param T $value
*
* @return T
*
* @template T
*/
static function ($value) {
return $value;
};
$convertValue = $this->createConvertValue($convertEmptyStringToNull, $rightTrimString);
$convertNumeric = $this->createConvertRow($convertValue, null);
$convertAssociative = $this->createConvertRow($convertValue, $case);
$this->convertNumeric = $this->createConvert($convertNumeric, $id);
$this->convertAssociative = $this->createConvert($convertAssociative, $id);
$this->convertOne = $this->createConvert($convertValue, $id);
$this->convertAllNumeric = $this->createConvertAll($convertNumeric, $id);
$this->convertAllAssociative = $this->createConvertAll($convertAssociative, $id);
$this->convertFirstColumn = $this->createConvertAll($convertValue, $id);
}
/**
* @param array<int,mixed>|false $row
*
* @return list<mixed>|false
*/
public function convertNumeric($row)
{
return ($this->convertNumeric)($row);
}
/**
* @param array<string,mixed>|false $row
*
* @return array<string,mixed>|false
*/
public function convertAssociative($row)
{
return ($this->convertAssociative)($row);
}
/**
* @param mixed|false $value
*
* @return mixed|false
*/
public function convertOne($value)
{
return ($this->convertOne)($value);
}
/**
* @param list<list<mixed>> $data
*
* @return list<list<mixed>>
*/
public function convertAllNumeric(array $data): array
{
return ($this->convertAllNumeric)($data);
}
/**
* @param list<array<string,mixed>> $data
*
* @return list<array<string,mixed>>
*/
public function convertAllAssociative(array $data): array
{
return ($this->convertAllAssociative)($data);
}
/**
* @param list<mixed> $data
*
* @return list<mixed>
*/
public function convertFirstColumn(array $data): array
{
return ($this->convertFirstColumn)($data);
}
/**
* Creates a function that will convert each individual value retrieved from the database
*
* @param bool $convertEmptyStringToNull Whether each empty string should be converted to NULL
* @param bool $rightTrimString Whether each string should right-trimmed
*
* @return callable|null The resulting function or NULL if no conversion is needed
*/
private function createConvertValue(bool $convertEmptyStringToNull, bool $rightTrimString): ?callable
{
$functions = [];
if ($convertEmptyStringToNull) {
$functions[] =
/**
* @param T $value
*
* @return T|null
*
* @template T
*/
static function ($value) {
if ($value === '') {
return null;
}
return $value;
};
}
if ($rightTrimString) {
$functions[] =
/**
* @param T $value
*
* @psalm-return (T is string ? string : T)
*
* @template T
*/
static function ($value) {
if (! is_string($value)) {
return $value;
}
return rtrim($value);
};
}
return $this->compose(...$functions);
}
/**
* Creates a function that will convert each array-row retrieved from the database
*
* @param callable|null $function The function that will convert each value
* @param int|null $case Column name case
*
* @return callable|null The resulting function or NULL if no conversion is needed
*/
private function createConvertRow(?callable $function, ?int $case): ?callable
{
$functions = [];
if ($function !== null) {
$functions[] = $this->createMapper($function);
}
if ($case !== null) {
$functions[] = static function (array $row) use ($case): array {
return array_change_key_case($row, $case);
};
}
return $this->compose(...$functions);
}
/**
* Creates a function that will be applied to the return value of Statement::fetch*()
* or an identity function if no conversion is needed
*
* @param callable|null $function The function that will convert each tow
* @param callable $id Identity function
*/
private function createConvert(?callable $function, callable $id): callable
{
if ($function === null) {
return $id;
}
return /**
* @param T $value
*
* @psalm-return (T is false ? false : T)
*
* @template T
*/
static function ($value) use ($function) {
if ($value === false) {
return false;
}
return $function($value);
};
}
/**
* Creates a function that will be applied to the return value of Statement::fetchAll*()
* or an identity function if no transformation is required
*
* @param callable|null $function The function that will transform each value
* @param callable $id Identity function
*/
private function createConvertAll(?callable $function, callable $id): callable
{
if ($function === null) {
return $id;
}
return $this->createMapper($function);
}
/**
* Creates a function that maps each value of the array using the given function
*
* @param callable $function The function that maps each value of the array
*/
private function createMapper(callable $function): callable
{
return static function (array $array) use ($function): array {
return array_map($function, $array);
};
}
/**
* Creates a composition of the given set of functions
*
* @param callable(T):T ...$functions The functions to compose
*
* @return callable(T):T|null
*
* @template T
*/
private function compose(callable ...$functions): ?callable
{
return array_reduce($functions, static function (?callable $carry, callable $item): callable {
if ($carry === null) {
return $item;
}
return /**
* @param T $value
*
* @return T
*
* @template T
*/
static function ($value) use ($carry, $item) {
return $item($carry($value));
};
});
}
}